- ...there is no evidence at all in Gusev crater for the paleolake deposits they had hoped to find there. "The cratered plains of Gusev are dominated by aeolian processes. THe rock distributions can be related directly to the impacts that occurred here. Liquid water has not shown its face ANYwhere except in alteration rinds; this has been dry and dessicated since the lava flows formed in the Hesperian. If you go to any place on Mars where the rock crystallization age is equal to the crater age, this is what it will look like."

- ...the craters that Spirit has seen, at every scale from Bonneville to the tiniest "hollow" only 40 centimeters across, is very shallow, with a depth-to-diameter ratio of less than 1 to 10. Though some are certainly filled with sediment, the freshest look reasonably fresh, with rocky bottoms. The shallowness, Matt argued, strongly suggested that every crater that Spirit has seen to date is a secondary. (That means that they didn't form from an original meteorite hit; they formed when the spray of debris from a single large meteorite hit fanned out and splatted into the ground. The lower speeds at which secondary craters form result in the shallower depths.) This observation "has very important implications for age dating using very small craters," Matt finished. What he's implying is that people may be significantly over-counting craters on Martian surfaces similar to the one that Spirit's sitting on.

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